Welcome aboard sparkie! I can't hear that now and not think of Ron White.

I do not own, nor use polymer mags, but I'm quick to repeat what others have said: Don't store them too long, fully loaded, so as not to put too much strain on the lips, lest their spacing slowly get loose. Sorry to hear about you experiencing feed problems with metal, single stack mags. Most seem to be hit or miss without a little tweaking as discussed ad infinitum in this thread.

Hoot

In Theory, there is no difference between theory and practice. In Practice, there is.

sparkie259 wrote:I'm new here and also to the 450B. I just put mine together. It seems the big issue with it is with magazines and feeding them. I''ve seen a lot of chatter on using single stack followers in 223 mags. I tried that and it didn't work that great for me. There were cycling issues and LRH didn't work. Last night I was working on another AR and picked up the magazine and figured I just give it a try. It was a Lancer L5AWN 20 round 223 mag. With no mods to the mags I was able to load 6 rounds. Just got back from the range and they worked great. No cycling issues and LRH worked just fine. I was using factory Hornady FTX bullets.Maybe this has been tried by someone else but I either didn't see the thread. Maybe I just missed it. Either way I just wanted to throw this out to the group.

Whenever someone is looking for mags, I always recommend trying a standard .223 / 5.56 mag (not necessarily polymer, but whatever you have laying around) before beginning an exotic magazine search. I have found they work almost all the time, even with the double stack follower.

FWIW, I had problems with my factory mag. It randomly ejected 3 cartridges while walking from my truck to the shooting station. Then, when fired, it combination-failed with a stovepipe, and trying to chamber 2 rounds. It did that twice. I have contacted Bushmaster about it, and they are sending me a new mag.

Luckily, I had also purchased a Bartz aftermarket mag, and that went through 30 rounds flawlessly (in both the upper and magazine).

Kelvarr wrote:FWIW, I had problems with my factory mag. It randomly ejected 3 cartridges while walking from my truck to the shooting station. Then, when fired, it combination-failed with a stovepipe, and trying to chamber 2 rounds. It did that twice. I have contacted Bushmaster about it, and they are sending me a new mag.

Luckily, I had also purchased a Bartz aftermarket mag, and that went through 30 rounds flawlessly (in both the upper and magazine).

Welcome Aboard OM!

Did you compare the amount of spring tension in the two magazines. IMHO, Bushmaster and several other companies use way too much spring tension which again IMHO, contributes to many users problems with feeding. It only needs to be strong enough to lift the last round properly into place and then catch the BHO when its empty. Hopefully the new one they send you has actually been tested in a real weapon.

Hoot

In Theory, there is no difference between theory and practice. In Practice, there is.

Kelvarr wrote:FWIW, I had problems with my factory mag. It randomly ejected 3 cartridges while walking from my truck to the shooting station. Then, when fired, it combination-failed with a stovepipe, and trying to chamber 2 rounds. It did that twice. I have contacted Bushmaster about it, and they are sending me a new mag.

Luckily, I had also purchased a Bartz aftermarket mag, and that went through 30 rounds flawlessly (in both the upper and magazine).

Welcome Aboard OM!

Did you compare the amount of spring tension in the two magazines. IMHO, Bushmaster and several other companies use way too much spring tension which again IMHO, contributes to many users problems with feeding. It only needs to be strong enough to lift the last round properly into place and then catch the BHO when its empty. Hopefully the new one they send you has actually been tested in a real weapon.

Hoot

Thanks! I've been browsing for quite some time, and thought I registered before!

I did not test the amount of spring tension other than by using my fingers to push on the follower, and it feels about the same.

I my case though, the feed lips are too far apart. The cartridge casing can freely pop up right between the feed lips, without having to be forced forward by the bolt. When the Bartz and Bushmaster magazines were held so that feed lips were directly compared (one mag upside down on top of the other), the Bartz mag feed lips were a little longer, and bent in/down more, so they actually held the cartridge in place (you can't eject the cartridge straight up without damaging the magazine in the Bartz).

SGWINK wrote:My Smith says that those rings need ALL TO BE rotated so NONE of them align with relativity to one another - meaning each ring should be rotated in positions so that no openings align...

I just completed a two day AR carbine course with a former Navy Seal instructor. According to him, alignment of the rings is not necessary. Originally, the AR was designed with a single ring; the other two were added for redundancy. I admit that I usually try and make sure they are not all aligned, when I clean the BCG, but it is really not necessary.